Rotary material reducing machine



Aug. 1, 1933. w. J. ARMSTRONG ROTARY MATERIAL REDUCING MACHINE Filed July 25, 1930 2 Sheets-Sheet. l

/N VE N TOR Wa/fer J Hrmfifrony.

G a a nu a L F: a G z a U E g Aug. 1, 1933. w. J. ARMSTRONG 1,920,946

ROTARY MATERIAL 4 REDUC ING MACHINE Filed July 25, 1930 2 Sheets-Sheet. 2

/NVENTOR Wa/fer J Arms fro/7.

% W @ww Patented Aug. 1, 1933 UNITED STATES rarest Walter J. Armstrong, Columbus, Ohio, assignor to The Jefirey Manufacturing Company, Columbus, Ohio, a Corporation of Ohio Application July 25, 1930. Serial No. 470,738

18 Claims.

The present invention relates to a machine particularly adapted for use in shredding fibrous materials such as straw in bales, corn stalks, wood chippings, bagasse, pulp in laps or sheets,

5 and other similar materials not of high specific gravity but heavy in the masses ordinarily fed to the machine, for example, wet wood chips.

The ordinary type of swing hammer machine customarily used in the reduction of such materials possesses certain defects which considerably impair its efficiency. Either the hammers have been too light to properly support the fed material, take the impact shocks common with intermittent feed, and out through the material in the screen bar section without being forced back out of radial position, or they have been so heavy that proper shredding or cutting action has not been effected due to the thickness of the hammers and the forcing of material thereby through the screen bars before it is sufficiently reduced.

In a machine of which I am aware, the disadvantages of the type of machine above discussed have been largely eliminated due to the use of a combination of flotation'and reducing hammers. In this improved machine, the flotation hammers present greater resistance to tangentially directed impacts as compared to the reducing hammers, and thus are enabled to float the fed mass of material until it is sufiiciently broken up to be properly engaged by the reducing hammers. In order to obtain the differential rigidity of the hammers, the flotation hammers may be rigidly mounted, the reducing hammers being in the form of swing hammers.

I have found that operation of a machine of the above described improved type may be favorably affected if the reducing hammers have a somewhat greater normal radial projection than the flotation hammers. I have also found that results are improved if the reducing hammers, which are alternated with the flotation hammers around the rotor, are set closer to the preceding flotation hammers than to the succeeding, and in this relation the normal radial projection of the hammers may be the same or diiierentiated as above described.

In the accompanying drawings, I have illustrated a number of preferred hammer arrangements, although it will be understood that this showing is intended to be illustrative and unrestrictive of the invention, since other arrangements are possible within the scope of my invention.

In the drawings 7 Fig. l is a cross section of a machine embodying the present invention;

Fig. 2 is a developed plan of the rotor of Fig. 1;

Fig. 3 illustrates a modified hammer arrangement; h

Fig. 4 is a section of a rotor embodying a modified form of hammer; I

Fig. 5 is a developed plan of the rotor of Fig. 4;

Fig. 6 illustrates a modified arrangement of hammers, and

Fig. 7 is a section through a rotor embodying a still further relative arrangement of the hammers.

Referring to the drawings and first of all to Figures 1 and 2, reference numeral 10 designates generally a rotor casing provided with an up wardly open hopper 11, a braher bar 12, and a screen bar section 13. A shaft 14 is arranged for rotation in the casing and supports a rotor body comprising a series of circular co-axially spaced discs 15 keyed thereon and retainedin spaced position by means of spacin collars 16, the discs being provided with aligned apertures around the shaft in which are supported mounting rods 17.

In alternating arrangement around the rotor body and mounted on rods 17 are a number of flotation hammers 18 and reducing hammers 19. As here shown, the flotation hammers are rigidly mounted on the discs by means of twoarms each of which is engaged by a 'rod 17, the hammers having a third radially projecting arm. The reducing hammers are each mounted on a single rod so as to be able to swing freely thereon.

As shown in Fig. 2, hammers 18 and 19 are arranged in alternating rows extending axially of the rotor and are of a size to substantially fill the rod spaces between the discs. As is most clearly seen from Fig. l, the radial projection of hammers 18 is substantially less than the radial projection of hammers 19 when the latter are in the rigid hammers 18 of the adjacent rows. Here may be of the same length. It will be underagain the radial projection of the swing hammers is greater than the normal radial projection of the rigid hammers as indicated in Fig. 1. The arrangement of Fig. 3 is used when the feed is not extremely heavy and a coarser product is desired.

According to Figs; 4 and 5, the machine casing and rotor body are of the same standard size and form as shown in Fig. 1, but the hammers are much thinner than those shown in Fig. 2 and only partially fill the disc spaces as determined by the disc spacing collars. While the thickness of the hammers may be varied to meet requirements, they are shown in Figs. 5 and 6 as being substantially half the width of the hammers of Fig. 2. 1

In Figs. 4 to 6, the flotation hammers are designated at 20 and the reducing hammers at 21. According to Fig. 5, hammers 20 and 21 are arranged in alternating rows in the axial direction of the rotor, all the rod spaces being occupied. In order to position the hammers between the discs, spacing elements or collars 22 are strung on the, rods. Referring to the upper row of hammers 20 in Fig. 5, it will be noted the collars 22 are arranged so as to position the hammers against the right hand faces of the disc, while the collars 2'2 associated with the swing hammers 21 position the latter against the left hand disc faces. Thus the two sets of hammers are maintained in non-tracking relation and chattering is prevented. This arrangement is used when the material is comparatively light in itself and the feed is not too heavy, and when it is desired to secure a fine product.

According to Fig. 6, some of the rod spaces are 'left free with the result that each adjacent two rows of rigid and swing hammers are staggered' relative to the succeeding two rows, thus forming groups of hammers, each comprising a leading rigid hammer and a trailing swing hammer in non-tracking relation. Further, the hammersbf each group are in non-tracking relation. This arrangement is desirable in reducing more friable material and, of course, the feed cannot be so heavy as when the other arrangements are used.

In Figs. 5 and 6, boththe rigid and swing hammers are shown asbeing of substantially the same thickness, but it is obvious that they may beof difierent thicknesses and maybe variously arranged on the rods to meet various conditions. It will be understood that in bothv Figs. 5 and 6 the rig d and swing hammers are assumed to have the different radial projections as indicated in Fig. 4.

In Fig. 7, the rigid hammers are indicated at 23fand the swing hammers at 24, and it will be noted that the latter are supported on the trailing rod of the two rods which support each rigid hammer, thus leaving a vacant rod between each pair of hammer mounting rods. rangement brings each swing hammer closer to the preceding rigid hammer than to the succeeding rigid hammer. This relative arrangement of the rigid and swing hammers enables the former to effectively guard the latter against impact shocks and to virtually carry the peak In the arrangement according. to Fig. '7, the hammers may be of full width and arranged in alternating -disc spaces or they may be of half width or. less, and both arranged in the same disc space, and, further, both sets of hammers This arstood that this figure is only intended to illustrate the closely trailing relation of the swing hammers to the rigid hammers.

While I have described the present invention as being particularly applicable to machines designed for shredding, it is to be understood that the invention is applicable also to pulverizing and crushing machines and I do not limit myself in this respect.

I claim:

1. In a machine of the class described, a casing having an upwardly directed feed opening,

a rotor body in said casing, said rotor body comprising a number of spaced co-axial discs and a series of rods supported about the of the discs in apertures of said discs, a number of radially projecting flotation hammers mounted on said rods between the discs for floating material fed thereto through said opening, and a number of centrifugally projected material reducing hammers pivoted to said rods between the discs and 7 having relatively great 'yieldability under tangentially directed impacts as compared to the flotation hammers, said flotation and material reducing hammers only partially filling the spaces between their adjacent discs, the reducing hammers having a normally greater radial projection than the flotation hammers, said hamme "s being arranged in alternating rows. extending axially of the rotor body with the hammers of each two adjacent rows staggered relative to the hammers of the next two adjacent rows to form groups each'comprising a leading flotation hammer and a trailing material reducing harnmer. f v k 2. In a machine of the class described, a casing having an upwardly directed feed opening,

a rotor body in said casing, said rotor body comprising a number of spaced co-axial discs and a series of rods supported about the axis of the discs in apertures of said discs, a number of radial y projecting flotation hammers mounted terial fed thereto through said opening, and a number of centrifugally projected material reducing hammers pivoted to said rods between the discs and having relatively great yieldability under tangentially directed. impacts as compared to the flotation hammers, said flotation and material reducing hammers only partially filling on said'rods-between the discs for floating mathe spaces between theirradjacent discs, the reducing hammers having-a normally greater radial projection than the flotation hammers, said hammers being arranged in alternating rows extending axially of the rotor body, and spacing elements positioning said hammers relative to their adjacent discs with adjacent flotation and material reducing hammers between the same discs in non-tracking relation.

3. In a machine of the class described, a rotor body, rigidly mounted hammers projecting radially from said rotor and acting to float material on the rotor upon rotor rotation, and

terial on the rotor upon rotor rotation, and swing hammers pivoted to said rotor and adapted to be substantially radially projected upon rotor rota tionto yield under tangential reducing impact upon said material, the rigid hammers and swing hammers beingarranged in alternating rows extending axially of the rotor body, the swing hammers having a-normally greater radial projection than the flotation hammers. I j

5. In amachine of'the class described, a rotor body, rigidly mounted hammers projecting radially from said rotor, and swing hammers pivoted to said rotor and adapted to be substantially radially projected upon rotor rotation, the rigid hammers and swing hammers being arranged in alternating rows extending axially of the rotor body with the hammers of each row staggered relative to the hammers of the adjacent rows, the

swing hammers having a normally greater radial projection than the flotation hammers.

6. In a machine of the class described, a rotor body comprising a number of spaced co-axial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs and only partially filling the spaces between their adjacent discs, the swing hammers having a normally greater radial projection than the flotation hammers.

'7. In a machine of the class described, a rotor body comprising a number of spaced co-axial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs and only partially filling the spaces between their adjacent discs, and spacing elements positioning said swing hammers relative to their adjacent discs, the swing hammers having a normally greater radial projection than the flotation hammers.

8. In a machine of the class described, a rotor body comprising a number of spaced co-axial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs, the rigid and swing hammers only partially filling the space between their adjacent discs, the swing hammers having a normally greater radial projection than the flotation hammers.

9. In a machine of the class described, a rotor body comprising a number of spaced co-axial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs, the rigid and swing hammers only partially filling the spaces between their adjacent discs, and spacing elements positioning said hammers relative to their adjacent discs, the swing hammers having a normally greater radial projection than the flotation hammer.

10. In a machine of the class described, a rotor body comprising a number of spaced coaxial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs, the rigid and swing hammers only partially filling the spaces between their adjacent discs, said hammers being arranged in alternating rows extending axially of the rotor body, the swing hammers having a normally greater radial projection than the flotation hammers." I

11. In a machine of the class described, a rotor body comprising a number of spaced coaxial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs, the rigid and swing hammers only partially filling the spaces between their adjacent discs, said hammers being arranged in alternating rows extending axially of the'rotor body with the hammers of each two adjacent rowsstaggered relative to the hammers of the next two adjacent rows to form groups each comprising 'a leading rigid hammer and a trailing swing hammer, the swing hammers having a normally greater radial projection than the flotation hammers.

12. In a machine of the class described, a rotor body comprising a number of spaced co-axial discs and a series of rods supported about the axis of the discs in apertures of said discs, hammers rigidly mounted on said rods between the discs, and swing hammers pivoted to said rods between the discs, the rigid and swing hammers only partially filling the spaces between their adjacent discs, said hammers being arranged in alternating rows extending axially of the rotor body, and spacing elements positioning'said hammers relative to their adjacent discs with adjacent rigid and swing hammers between the same discs in non-tracking relation, the swing ham-' mers having a normally greater radial projection than the flotation hammers.

13. In a machine of the class described, a rotor body, hammers rigidly mounted to said rotor body and swing hammers pivoted to the rotor body, the rigid and swing hammers being alternated around the rotor body, the swing hammers being pivoted to the rotor body at points closer to the preceding than to the succeeding hammers.

14. In a machine of the class described, a rotor body, hammers rigidly mounted to said rotor body and swing hammers pivoted to the rotor body, the rigid and swing hammers being alternated around the rotor body, the swing hammers being pivoted to the rotor body at points closer to the preceding than to the succeeding hammers and having a normally greater radial projection than the rigid hammers.

15. In a machine of the class described, a rotor body comprising a number of spaced apart coaxial discs and rods supported in apertures of said discs about their axis, rigid hammers projecting from the rotor body and having portions engagedby a plurality of adjacent ones of said rods, and swing hammers pivoted on the trailing ones of the rigid hammer supporting rods.

16. In a machine of the class described, a rotor body comprising a number of spaced apart coaxial discs and rods supported in apertures of said discs about their axis, rigid hammers projecting from the rotor body and having portions engaged by a plurality of adjacent ones of said rods, and swing hammers pivoted on the trailing ones of the rigid hammer supporting rods, there being a vacant rod intermediate adjacent sets of hammer supporting rods.

17. In a machine of the class described, a rotor body comprising a number of spaced apart coaxial discs and rods supported in apertures of said discs about their axis, rigid hammers projecting from the rotor body and having portions engaged by a plurality of adjacent ones of said 7 a. ii

engaged-by ,a pluralityof adjacent ones .of said Q rods, ,-a,nd,swing hammers pivoted-on the trailing ones not the Trigid hammer supporting rods, there being a vacant rod intermediate adjacent sets of hammer supporting rods, the swing hammers having normally'a vgreater radial projection than the rigid hammers. I

- WALTER, J. ARMSTRONG. 

